Both 1-component and multi-component (but preponderantly, 2-component) chemistries, which include adhesives, sealants, potting compounds, anchoring pastes, and the like (represented by such chemistries as epoxies, polyurethanes, polysulfides, acrylics, silicones, polyesters, etc.), are used throughout the world for bonding, sealing, encapsulating, anchoring and coating many different items in construction, manufacturing, aerospace, medical, transportation, consumer and other market areas. With 2-component chemistries, the two reactive materials are maintained separate from one another and unmixed until just prior to use. To use 2-component chemistries, the components are often mixed in a separate container and applied either using an automatic dispenser or manually. Alternatively, one frequently uses a specialized or custom dispenser having parallel cartridges to dispense the 2-component chemistries with the mixing being accomplished by a static mixer inside the dispensing nozzle.
Despite the inconvenience of having to mix 2-component chemistries or purchase specialty components prior to use, the industry considers 2-component chemistries superior in performance and prefers using 2-component chemistries in most applications. Generally, the industry prefers 2-component chemistries because they frequently have better physical and chemical properties than 1-component chemistries. However, while 2-component chemistries are currently and widely used in certain industries (both from bulk containers and from pre-loaded specialized packaging), such use has been restricted to using relatively expensive and relatively specialized application or dispensing equipment. Therefore, there is a need to provide a reactive-chemical dispensing cartridge packaging, which could be used for both 1-component or multi-component chemistries, that is capable of use in common, standard, inexpensive caulking guns of the type generally found in hardware stores, home centers, paint stores and the like.
It has been recognized previously by such inventors as, for example, Creighton (U.S. Pat. No. 3,323,682), Maziarz (U.S. Pat. No. 5,535,922) and Konuma (U.S. Pat. No. 5,593,066) that it would be advantageous to have a package that permitted the dispensing of 2-component chemistries from common, standard caulking guns, so that all users in all markets could take advantage of the high performance provided by such 2-component chemistries, while enjoying the low cost and ready availability of such standard dispensing equipment. Yet, none of the prior invention disclosures disclose a package design that is: uncomplicated to use by the applicator, technically feasible to manufacture (especially regarding the factory-filling of such containers with high viscosity, pasty materials), sufficiently rugged in its resistance to damage before use, economically viable overall, suitable for dispensing even high viscosity sealants or adhesives, easily recyclable, or comprehensively practical enough to be introduced into or gain acceptance by commercial markets.
Creighton, for instance, discloses no practical design, feasible method of manufacturing, or reasonable method of factory-filling his package with adhesives or sealants (and, consequently, this design has never been commercialized). The Maziarz design, while having found some commercial success, requires the use of a separate rigid adapter to permit the primary all-rigid package to be used in a standard caulking gun, and the maximum volume of material that can be placed into this primary package is only about ¼ to ½ the volume normally possible from packages typically used in such dispensing equipment (and the package cannot be readily recycled). The Konuma design also requires the use of a separate rigid adapter in order to be usable in a standard, common caulking gun. Also, the Konuma design involves a primary collapsible-film package that is much more prone to damage during transport, storage, adapter-insertion or use than typical rigid cartridges that are widely used in standard, common caulking guns.
One commercial package and product currently being sold in Europe (by Artur Fischer (UK) Ltd.—named “FIP 300 SF”) has a 2-part “sausage” or “chub”, sealed at each end with a strong metal clip, inserted into a rigid plastic caulking cartridge that can be installed in a common, standard caulking gun. Before use, the user pulls one end of the collapsible sausage, with a metal clip attached to it, through the treaded cartridge outlet port and cuts the metal clip is cut off with a knife—thus opening the sausage for dispensing. Then, the user screws a nozzle on the threaded outlet a, with the nozzle typically having a static mixer inside, and mixes/dispenses the 2-component, low viscosity, polyester anchoring mortar.
Several problems exist with this design. First, because the plastic film of the sausage is pulled into and left inside the narrow outlet of the cartridge, the wad of plastic film bunched up inside the outlet port can greatly restrict the flow of the chemical components during dispensing—which may only be a moderate problem if the viscosity of the fluids is very low (as in the case of this commercial “FIP 300 SF” product), but can be a great problem if the product viscosity is high and the product is pasty. Second, it is possible for the chemical components to contact and foul portions of the interior of the rigid cartridge either during dispensing or during spent-sausage removal from the rigid cartridge—making cartridge reuse or recycling very problematic or impossible, and messy in either case. Third, the rigid cartridge has several avenues of gaseous fluid communication between the outside atmosphere and the interior of the package that could partly endanger the shelf life of certain reactive sealants or adhesives during prolonged storage.
It is important to note that many previous inventors have described and, in some cases, commercialized 2-component specialized packaging that is suitable for use only in specialized, relatively expensive dispensing equipment, but not suitable for use in common, standard and inexpensive caulking guns. The commercial market place and the patent literature are replete with many instances of such inventions. Examples of such designs can be found in the works of Blette (U.S. Pat. No. 5,386,928), Sauer (U.S. Pat. No. 5,897,028), Koga (U.S. Pat. No. 6,019,251), Camm (U.S. Pat. No. 5,918,770), Vidal (U.S. Pat. No. 6,047,861), Anderson (U.S. Pat. No. 4,366,919), Penn (U.S. Pat. No. 4,846,373), Schiltz (U.S. Pat. No. 5,566,860), Giannuzzi (U.S. Pat. No. 5,184,757), etc. The present invention, however, permits the use of such reactive materials in simple, affordable and readily available caulking guns, so that virtually everyone, in all industries, can enjoy the benefits of said reactive materials at a low overall cost.
Notably, previous attempts at creating a practical 2-component package for this use have not addressed the need to be able to factory-fill, in a practical manner, such packaging with high viscosity, pasty adhesives and sealants. Either this issue has not been dealt with at all in previously disclosed designs, or, when addressed, the methods outlined or implied have not been feasible. For instance, Keller (U.S. Pat. No. 5,647,510) describes a device that has some similarities to the present invention, but Keller's design calls for the collapsible-film pouches within the device to be attached to one or more relatively small diameter dispensing nozzles that cannot be practically used for filling the pouches causing the pouches to be filled from the rear of said pouches (i.e., at the piston end)—as virtually all previous designers appear to have done, with such a filling approach not being readily or easily accomplished in a practical way. (Notice, in the context of this application, collapsible-film pouches and collapsible packages are generally used interchangeably). In particular, filling pouches from the rear and non-attached end can cause pinching, a crimping of the pouches, which inhibits the dispensing of the chemicals contained in the pouches. Furthermore, by filling the pouches from the rear, it is difficult, if not impossible, to completely fill the pouches with chemicals to fully use the possible volume.
Keller is a useful example of problems associated with conventional methods for filling chemicals in collapsible-film package (and possible explains why none have been successfully commercialized). For example, by filling the package from the rear (which is conventional and exemplified by Keller), the pouch must be held or gripped at the package edge. The gripping to effectuate a filling procedure can damage or weaken the film at the edge and make the edge prone to failure. Further, when filling the packages external to a cartridge body (again conventional and exemplified by Keller and the other cited prior art), they are susceptible to bulging along the length.
When the package bulges, it becomes difficult to insert the bulging package in the cartridge body without damaging the package. Even assuming the package was filled without damaging the edges, and inserted in the cartridge body without damaging the package, sealing the open end of the package (i.e., the end that was filled) is problematic at best. In particular, gathering the open end of the package to seal the package with a traditional clip would likely cause voids or unused space, which is not efficient. Alternatively, using a seal, such as a heat seal, runs the risk of fouling the sealing surface with the chemicals and causing a weaker seal. Finally, and specific to the Keller disclosure, the plunger is not removable from the rear end of the cartridge body (see sealing ring and lips in Keller FIGS. 1, 2, 5, 6, and 7). Thus, the packages in Keller must be filled external to the cartridge body and then inserted in the body, which exemplifies the methods of conventional devices.
If the issue of efficiently filling such packages at the factory is not adequately addressed (and the factory-filling of such high viscosity, pasty materials as adhesives and sealants into hand-held, collapsible-film packaging is far more difficult than the factory-filling of low-viscosity, thin fluids), then it becomes difficult or impossible to economically produce such a package/product combination.
Moreover, the Keller device is not designed as a totally self-contained, integrated package, to be used in a common caulking gun; and, rather than recycling the main rigid cartridge body as taught below in the present invention, Keller's disclosed design calls for his rigid housing to be very stoutly built and aims at the repeated re-use of the stout, rigid housing by inserting fresh, collapsible-film pouches—which are relatively much more fragile and subject to damage, compared to integrated, mostly-rigid containers—into them in the field after the previously-used pouches have been emptied.
It is well known in the trade that 1-component, all-rigid, all-plastic polyethylene caulking cartridges typically used to contain many or most sealant and adhesive chemistries (and dispensed using common, standard caulking guns) are not currently used to contain 1-component, reactive, moisture-curable polyurethane sealants or adhesives. The reason is that such all-plastic containers do not provide sufficient moisture vapor permeability resistance to prevent premature and rapid curing of highly moisture sensitive polyurethanes during storage. Yet, because of the unsurpassed weather and damage resistance (as well as low cost) afforded by such rigid all-plastic containers (compared to the paperboard/aluminum foil cartridges most commonly used for such polyurethanes today), it would be advantageous to use such rigid, plastic containers for such products.